3,4-seco - 25,26,27 - trisnor-delta4(30)-dammarene-20-ol 3,24-dioic acid 24 20 lactone



United States Patent 3,483,225 3,4-SECO 25,26,27 'IRISN0R-A -DAMMARENE- 20-01 3,24-Dl0IC ACID 24- 20 LACTONE Gerald W. Krakower, Elizabeth, Josef Fried, Princeton, and David Walter Rosenthal, New Brunswick, N.J., assignors, by mesne assignments, to E. R. Squibb & Sons Inc., New York, N.Y., a corporation of Delaware No Drawing. Original application Sept. 13, 1963, Ser. No. 308,627, now Patent No. 3,422,134, dated Jan. 14, 1969. Divided and this application Feb. 7, 1968, Ser. No. 723,968

Int. Cl. C07c 173/00, 171/07; A61 27/00 US. Cl. 260-3435 1 Claim ABSTRACT OF THE DISCLOSURE This invention relates to the steroid, 3,4-seco-25,26, 27-trisnor-A -dammarene-ZO-ol 3,24-dioic acid 24 20- lactone, which has been found to possess antibiotic activity.

This application is a division of our application, Ser. No. 308,627, filed Sept. 13, 1963, now US Patent No. 3,422,134.

This invention relates to and has for its objects the provision of new physiologically active steroids, tetraand pentacyclic triterpenes and derivatives thereof, processes for their production and new intermediates useful in said preparation.

The novel compounds of this invention may be characterized as steroids or tetracyclic or pentacyclic triterpenes or derivatives thereof, possessing an A-ring structure represented by the following Formula I:

wherein each R is selected from the group consisting of hydrogen and lower alkyl (e.g. methyl); R represents hydroxy; R" represents lower alkyl (e.g. methyl) or hydrogen; and together R and R is selected from the group consisting of lower alkylene (e.g. methylene) and oxo (0:).

In the most preferable embodiment of this invention the compounds of this invention are those polycyclic compounds which may be substituted or unsubstituted in various positions, possessing the A-ring structure of Formula I and are further characterized by being selected from the group consisting of methylcholestanes, lanostanes, dammaranes, eburicanes, euphanes, tirucullanes, cycloartenane, cyclolandenanes, oleananes, ursanes, lupanes, taraxastanes, taraxanes, friedelanes, alnusenanes, and other like compounds.

The compounds of this invention have been found to possess antibiotic activity and may be employed for this purpose against a variety of pathogenic microorganisms. Among the organisms against which these compounds may be employed is included Staphylococcus aureus. The compounds of this invention may be administered for the purpose of this invention topically, parenterally or perorally. Thus, they may be administered by themselves, or in a pharmaceutical composition suitable for such purposes, for example, in an admixture of the compound and a suitable pharmaceutical carrier. Thus, the novel compounds of this invention may be administered in an ointment, cream, injectible suspension, tablet or capsule form.

3,483,225 Patented Dec. 9, 1969 The novel compounds of this invention may be prepared by the processes of this invention, employing as starting materials the saturated steroids having an A-ring structure represented by the following Formula II:

wherein R is as hereinbefore defined, and each Ra is selected from the group consisting of hydrogen and lower alkyl, at least one Ra being lower alkyl.

The starting materials which may be employed in the practice of this invention include such saturated poly cyclic compounds as the methylcholestanes (e.g. 4c:- methyl-3-cholestanone, 4,4-dimethyl-3-cholestanone); the lanostanes (e.g. lanostane-3-one); the dammaranes (e.g. 24,ZS-dihydrodipterocarpol); the eburicanes (e.g. methyl eburicane-3fi-ol-1l-one-Zl-oate); the euphanes (e.g. euphane-3B-ol-1l-one acetate); the tirucallanes (e.g. 8,9- oXido-tirucallane-3fi-ol acetate); the cycloartenones (e.g. cycloartenone); the oleananes (e.g. oleanane-3-one); the ursanes (e.g. a-amyrine oxide); the lupanes (e.g. lupane- 3-one); the taraxastanes (e.g. dihydrotaraxasterol); the taraxanes (e.g. dihydrotaraxerone); the friedelanes (e.g. friedeline); the alnusenanes (e.g. anusonyl acetate); and other like compounds.

The eburicane starting materials may be prepared in accordance with the teachings set forth in copending application Ser. N0. 198,425, filed May 29, 1962, in the names of Josef Fried and Gerald Krakower.

[In this application and in the appended claim, whenever in the formulae set forth herein a curved line (I) is employed in the linkage of atoms, it is meant to denote that the connected atom may be either in the alpha or beta position, as is determined in the respective compounds involved] The process by which the compounds of this invention may be prepared may be represented by the following equations, wherein R, R and Ra are as hereinbefore defined, and Z is lower alkylene and 0x0 (0:).

It is to be noted as stated hereinabove, that the starting materials employable in the practice of this invention must be saturated polycyclic compounds possessing an A-ring structure conforming to Formula II. In addition, these compounds may be substituted or unsubstituted in other positions of the molecule. It should also be remembered that the starting materials of this invention may also be prepared from the 3-hydroxy or 3-acyloxy substituted derivatives of those set forth hereinabove. In that case, the 3-acyloxy compounds may first be hydrolyzed, by any method known to the art, for the 3-hydroxy compounds, and the 3-hydroxy compounds may then be oxidized, by the procedures well known in the art, to yield the 3-keto starting materials possessing an A-ring structure conforming to that set forth in Formula II.

In the first step of the process of this invention the starting materials (Compounds II) are treated with a peracid, for example, m-chloroperbenzoic acid, to yield the 4-oxa-A-homo compounds (Compounds B) which are new compounds of this invention.

The 4-oxa-A-homo compounds (Compounds B) are then hydrolyzed as by treatment with an alcoholic alkali metal base, e.g. methanolic potassium hydroxide, to yield the 3,4-seco-4-hydroxy-3-oic acid compounds (Compounds C), which are new final products of this invention.

Compounds B may also be pyrolytically cleaved to directly yield the 3,4-seco-4-methyl compounds (Compounds D, wherein Z=CH which are also new final products of this invention.

Alternatively, Compounds C (wherein one Ra=H) may also be treated with an oxidizing agent, for example, chromic acid, to yield the 3,4-seco-4-keto-3-oic acid compounds (Compounds D, wherein Z=O=), which are also new compounds of this invention. These new Compounds D (wherein Z=O=) may also be obtained by treating Compounds D (wherein Z=CH with ozone.

The invention may be further illustrated by the following examples (all temperatures being in degrees centigrade).

EXAMPLE 1 4-oxa-4a,4a-dimethyl-A-homocholestane-3-one A solution of 414 mg. of 4,4-dimethyl-3-cholestanone (1 mole) and 345 mg. of m-chloroperbenzoic acid (2 moles) in 10 m1. of benzene-chloroform (3:1) is kept at 32 for 30 hours. The solution is diluted with chloroform, washed with potassium iodide solution, 5% sodium bisulfite solution, water, 5% sodium bicarbonate solution and water, dried and evaporated to give 415 mg. of crude material. Two recrystallizations from methanol gives 146 mg. of analytically pure 4-oxa-4a,4a-dimethyl-A-homocholestane-3-one, M.P. 123-124; [001 --1.7;

REE; 5.79, 5.85u (sh) Analysis.Calcd for C H O C, 80.87; H, 11.70. Found: C, 80.91; H, 11.71.

EXAMPLE 2 3,4-seco-4,4-dimethylcholestane-4-ol-3-oic acid A solution of 100 mg. of the 4-oxa-4a,4a-dimethyl-A- homocholestane-3-one in ml. of 5% methanolic potassium hydroxide is kept at room temperature for four and one-half hours. The pH is adjusted to 4.5 and after dilution with water the methanol is evaporated. The aqueous suspension is extracted with chloroform and the chloroform washed with water, dried, and evaporated to give 99 mg. of the crude acid. Recrystallization from methanol gives 68 mg. of 3,4-seco-4,4-dimethylcholestane-4- ol-3-oic acid (HIa), M.P. 137-1395. The analytical sample has M.P. 137.5139; [M +27";

Analysis.Calcd for C H O C, 77.62; H, 11.68. Found: C, 77.88; H, 11.83.

EXAMPLE 3 4a-methylcholestanone 4u-methylcholestanone is prepared by the reduction of 4a-methylcholestenone with lithium in liquid ammonia according to the procedure of Mazur and Sondheimer 4 (I. Am. Chem. Soc., 80, 5228 [1958]). The product from a 200 mg. run shows a strong hydroxyl group in the infrared and is reoxidized with Jones reagent and chromatographed. The pure product melts at 121-122 (block).

EXAMPLE 4 4-oxa-4au-methyl-A-homocholestane-3 -one Nuiol max.

The mother liquors are analyzed by vapor phase chromotography and shown to be at least 65% pure. Isolated yield, 82%. Yield calculated on the basis of product present in the mother liquor, 93%.

Analysis.--Calcd fOl C2 H4gO3'CH3OHI C, H, 11.68. Found: C, 77.72; H, 11.18.

EXAMPLE 5 3,4-seco-(4S)-4-methyl-4-hydroxy-3-cholestanoic acid Thirty mg. of 4-oxa-4aa-methyl-A-homocholestan-3-one is suspended in 10 ml. of 1.2 N potassium hydroxide in 98% methanol and shaken at room temperature overnight. The clear solution is then acidified carefully with dilute hydrochloric acid to pH 3.5 and extracted thoroughly with chloroform. The chloroform extract is washed with saturated sodium chloride solution and dried over sodium sulfate. Evaporation gives a white gel which weighs 30 mg. Seven mg. of this product crystallizes poorly to yield 5 mg. of poorly formed crystals from ether-hexane. The crystals are washed further with hexane and dried to give 3,4-seco-(4S)-4-methyl-4-hydroxy-3- cholestanoic acid, M.P. -1l5;

max.

Analysis.-Calcd for C H O C, 77.36; H, 11.59; neutralization equivalent, 434. Found: C, 77.51; H, 11.53; neutralization equivalent, 439.

EXAMPLE 6 3,4-seco- (4S) -4-methyl-4-hydroxy-3-cholestanoic acid 4-oxa-4aa-methyl-A-homocholestane-3-one (46 mg.) derived from 4or-methylcholestanone is hydrolyzed with 20 ml. of 1.5 N KOH in methanol at room temperature for 16 hours. The hydroxy acid obtained by acidification and extraction with chloroform is then methylated with diazomethane in ethermethanol to furnish the crystalline methyl 3,4-seco-(4S)-4-hydroxy-4-methyl-3-cholestanoate (49 mg). This substance is shown to be completely homogeneous by thin layer chromatography. After crystallization from methanol 37 mg. of M.P. 103-104 is isolated, [a] +14 (c., 0.70 in CHCL Analysis.Calcd for C H O C, 77.62; H, 11.68. Found: C, 77.54; H, 11.67.

The ester thus obtained is then saponified as described in Example 5 and the pure 3,4-seco-(4S)-4-methyl-4- hydroxy-3-cholestanoic acid isolated by extraction with chloroform.

EXAMPLE 7 Methyl 3,4-seco-4-oxo-4-methyl-3-cholestanoate Methyl 3,4 seco (4S) 4 hydroxy 4 methyl 3- cholestanoate (27.5 mg.) is dissolved in acetone (20 ml.) and oxidized with chromic acid and sulfuric acid in acetone. After decomposition of the excess oxidant with methanol, the product is taken up in chloroform and water, extracted with more chloroform and the chloroform extract extracted with saturated sodium chloride solution and evaporated to give 22 mg. of an oil which crystallizes on standing. Recrystallization from methanol 5 gives methyl 3,4-seco-4-oxo-4-methyl-3-cholestanoate possessing the following properties: M.P. 74-75; [a] -5 (c., 1.51 in CHCL max. 5.85,

Analysis.Calcd for C H O C, 77.97; H, 11.28. Found: C, 77.97; H, 11.33.

EXAMPLE 8 3,4-seco-4-keto-4-methyl-3-cholestanoic acid ANuiOl 3.70 (broad), 6.88 1

Analysis.Calcd for C H O C, 77.62; H, 11.07. Found: C, 77.72; H, 11.18.

EXAMPLE 9 4-oxa-4aB-methy1-A-homocholestane-3-0ne max.

Analysis.Calcd for C H O C, 80.71; H, 11.61. Found: C, 80.69; H, 11.58.

EXAMPLE 10' 3,4-seco-( 4R) -4-methyl-4-hydroxy-3-cholestanoic acid Fifty mg. of 4-oxa-4a,8-methyl-A-homocholestan-3-one is hydrolyzed with 20 ml. of potassium hydroxide in methanol and treated according to the procedures set forth in Example 5. The resulting acid is recrystallized from methanol.

Its methyl ester is prepared with diazomethane and recrystallized from methanol, according to the procedures set forth in Example 6.

EXAMPLE 11 Methyl 3,4-seco-4-methyl-4-methylenecholestan-3-oate Fifty mg. of 4-oxa-4a,4a-dimethyl-A-homocholestane-3- one is placed into a small tube which is then evacuated and sealed under high vacuum. The contents of the tube is heated rapidly in a Woods metal bath to 200 and maintained at ZOO-210 for ten minutes. The tube is then cooled, opened and the material on the bottom of the tube (45 mg.) (5 mg. of starting material had sublimed) dissolved in 10 ml. of ether containing a drop of methanol. This solution is treated with excess ethereal diazomethane and evaporated. Crystallization from methanol gives 22 mg. of fine crystals, M.P. 64-65". From the mother liquor an additional 7 mg. of methyl 3,4-seco-4-methyl-4-methylenecholestan-3-oate (M.P. 67-68) is recovered by chromatography on alumina. Recrystallization of the first crop raises the M.P. to 6768.5; [a] -|-13.5 (c., 0.75 in CHCL max. .71, 6.10, 11.17

Analysis.Calcd for C H O C, 81.02; H, 11.79. Found: C, 80.92; H, 11.61.

EXAMPLE 12 3,4-seco-4-methyl-4-methylene-3-cholestanoic acid Seventy-one mg. of 4-oxa-4a,4a-dimethyl-A-homo-3- cholestanone is pyrolyzed in a sealed tube as described in Example 11. Recrystallization of the reaction mixture from methanol furnishes 28 mg. of the crystalline 3,4-seco- 4-methyl-4-methylene-3-cholestanoic acid possessing the following properties: M.P. l06108; [a] -|-15 (0., 0.99 in CHCL Analysis.Calcd for C H O C, 80.87; H, 11.70. Found: c, 80.81; H, 11.75.

EXAMPLE 13 Methyl eburicane-3, 1 1-dione-21-oate A solution of 778 mg. of methyl eburicane-3fi-o1-1 1- one-21-oate in 55 ml. of acetone is treated with a 10% excess of chromic acid and sulfuric acid reagent at room temperature. The excess chromic acid is decomposed with methanol and the reaction mixture diluted with ml. of water and 50 ml. of chloroform and the organic solvents evaporated in vacuo. The aqueous suspension is extracted with chloroform and the chloroform solution Washed with water, dried and evaporated to give 784 mg. of crude product. This is adsorbed on a column of 25 g. of neutral alumina and eluted with benzene and benzenechloroform (9:1) to give 734 mg. of methyl eburicane- 3,11-dione-2l-oate, which on recrystallization from methanol gives a first crop of 443 mg. M.P. 139140, and a second crop of 152 mg., M.P. 137-139". The analytical sample had M.P. 143-144; [a] +41.8 (CHCL max.

Analysis.-Calcd for C H O C, 76.75; H, 10.47. Found: C, 76.77; H, 10.43.

EXAMPLE 14 3,4-secoeburicane-4-ol-11-one-3,21-dioic acid 21-methyl ester 3 4-lactone Analysia-Calcd for C H O C, 74.37; H, 10.14. Found: C, 74.50; H, 10.32.

EXAMPLE 15 3,4-secoeburicane-4-ol-11-one-3,21-dioic acid 21- methyl ester A solution of 100 mg. of the lactone prepared in Example 14 in 10 m1. of 5% methanolic potassium hydroxide is kept at room temperature for six hours. The pH is adjusted to 4.5 and the reaction mixture diluted with water. The methanol is evaporated, the aqueous suspension extracted with chloroform and the chloroform solution washed with water, dried and evaporated.

The crude material is chromatographed on silica gel and the chloroform and chloroform-acetone (1:1) elutes combined and evaporated to give 39 mg. of the desired 3,4-secoeburicane-4-ol-1l-one 3,21 dioic acid 21 methyl ester. Neutralization equivalent: Calcd535; found 505.

EXAMPLE 16 3,4-secodammarane-4,20.-diol-3-oic acid A solution of 191 mg. of 24,25-dihydrodipterocarpol (0.43 mole, M.P. 97-98") and 590 mg. of m-chloroperbenzoic acid (3.45 moles) in 5 ml. of chloroform is kept at room temperature for 23 hours, After dilution with ml. of chloroform, the solution is washed with 5% potassium iodide solution, 5% sodium thiosulfate solution, water, 5% potassium bicarbonate solution and water, dried over sodium sulfate and evaporated to dryness in vacuo. Purification by thin layer chromatography on morin-impregnated alumina (Activity V) in a hexanechloroform (1:4) system and elution of the area gives 131 mg. of crude lactone.

The total crude lactone is hydrolyzed with ml. of 5% ethanolic potassium hydroxide at room temperature for six and one-half hours. After adjusting the pH to 4.5, the solution is diluted with water and the ethanol evaporated. The aqueous suspension is extracted with chloroform and the chloroform solution washed with water, dried and evaporated. Recrystallization of the crude product from methanol gives 85 mg. of 3,4-secodammarane-4, 20-diol-3-0ic acid, M.P. 175.5-176; +39.5 3);

AnaIysis.-Calcd for C H O C, 75.26; H, 11.37. Found: C, 75.19; H, 11.26.

EXAMPLE 17 3,4-seco-25,26,27-trisnordammarane-4,ZOE-diol-3,24- dioic acid 3 4,24+20 dilactone Following the procedure described in Example 16 for dihydrodipterocarpol but using 200 mg. of 25,26,27-trisnordammarane-3-one-20g-ol-24-oic acid lactone, there is obtained 3,4-seco-25,26,27-trisnordammarane-4,20-diol-3, 24-dioic acid 3+ 4,24 ZO-dilactone, which after recrystallization from methanol has the following properties: M.P. l78180 and 192194 (polymorphic modifications); [04], +104 (c., 0.75 in CHCL Analysis.Calcd for C -,H O (430.61): C, 75.31; H, 9.83. Found: C, 75.33; H, 9.78.

EXAMPLE 18 3,4-seco-25,26,27-trisnordammarane-4,20:-diol- 3,24-dioic acid Neutralization equivalent: 235, calcd 233.

The mother liquor from the above crystallization is recrystallized from acetone-hexane and furnishes 25 mg. of the 24 20-m0nolact0ne of 3,4-sec0-25,26,27 -trisnordammarane-4,20-diol3,24-dioic acid, with the following properties: M.P. 205207; [M +61 (c., 0.64 in CHCL Cir Analysis.Calcd for C H O (448.62): C, 72.28; H, 9.89. Found: C, 72.21; H, 9.84.

EXAMPLE 19 3,4-seco-25,26,27-trisnor-A -dammarene-20E-ol-3,24-

dioic acid 24+ 20-lactone Twenty-five mg. of 3,4-seco-25,26,27-trisnor-dammarene-4,20-diol- 3,24-dioic acid, 3- 4,24 20-dilactone is placed into a small tube, which is then evacuated and sealed. The tube is immersed in a Woods metal bath and maintained at 200-210 for ten minutes. The total prodnet is crystallized slowly from methanol to yield fine needles, M.P. 153454; [04 +44.5 (c., 0.83 in CHCL Yield12 mg. of 3,4 seco 25,26,27-trisnor-A -damrnarene-20-ol-3,24-dioic acid 24+20 lactone.

AnaIysis.-Calcd for C2qH4204'H2O (448.63): 72.28: H, 9.89. Found: C, 72.43; H, 9.98.

EXAMPLE 20 3,4-secolupane-4-ol-3-oic acid 3+4-lactone A solution of 0.426 g. of lupane- 3 -one (1 mmole) and 1.382 g. of m-chloroperbenzoic acid (8 mmoles) in 10 ml. of chloroform is kept at room temperature for 23 hours. After dilution with chloroform, the solution is washed with 5% potassium iodide solution, 5% sodium thiosulfate solution, water, 5% potassium bicarbonate solution and water, dried and evaporated. Two recrystallizations from acetone give 166 mg, of the lactone of 3, 4secolu-pane-4-ol-3cic acid, M.P. 192-195". The analytical sample has M.P. 193-196"; [111 +348";

mgr 5.79.1

Anulysis.Calcd for 0 mm,: c, 81.39; H, 11.38. Found: 0, 81.40; H, 11.38.

EXAMPLE 21 3,4-secolupane-4-ol-3-oic acid Analysis.Calcd for C H O C, 78.20; H, 11.38; NE. 460. Found: C, 78.08; H, 11.48; N.E. 457.

EXAMPLE 22 Methyl 3,4-seco-4-methylcholestane-4-one-3-oate A solution of 10 mg. of methyl 4-methyl-4-methylene- 3,4-seco-chloestane-3-oate in 2 ml. of ethyl acetate is ozonized with a large excess of ozonized oxygen at -40. The solution is allowed to stand at 40 for 15 minutes, warmed to room temperature and treated with 0.5 g. of zinc dust and a drop of glacial acetic acid after stirring for 10 minutes. The reaction mixture is filtered, washed with water, dried over sodium sulfate and evaporated to dryness. The reaction product is chromatographed on a thin layer of neutral alumina, Activity V, and eluted with 1:1 benzene:hexane. The band corresponding to the known reaction product (R =0.3) is isolated and rechromatographed in the same manner. The product is reisolated and crystallized from methanol. Yield: 2 mg.,

MP. 74-76". Recrystallization from methanol gives a product, M.P. 75-76, whose IR spectrum is identical and whose melting point is not depressed when mixed with an authentic sample of methyl 4-methyl-4-methylene- 3,4-seco-cholestane-3-oate, M.P. 7778, described in Example 7.

EXAMPLE 23 Substituting the various starting materials employable in the practice of this invention for the materials employed in the examples set forth above, and following the procedures of those examples, the results set forth in the following Table A are obtained:

TABLE A Starting Materials Final Products 1. Lenostane-3one 1a. 3,4-sec-1anostane-i-oLS-oic acid.

It). 3,4-sec0-A 4 (2E -lanostanc-tS-oic acid.

10. 3.4-seco28-nor-lanostane-4-one-3-oic acid.

2a. 3,4-seco-euphane-4 ol-3-oic acid 2b. 3,4 seco-A (2! -cuphene-3-oic acid.

20. It,4-seco-28mor-euphane-4one-3-oic 2. Euphane-3B-ol-11-one- (first oxidized to euphane- 3,11-dione).

acid.

3. 8,9-oxidotimcal1ane 3a. 8,9-oxido-3,4-seco-tirucallane-4-oI-3- oic ac 3b. 8,9-oxido-3A-seco-A (25 -timcallaue- 3-oic-acid.

3c. 8,9-oxido-3,4-seco-ZS-nor-tirucallane- 4-one-8-oic-acid.

4a. 3,4-seco-cycloa1tenane-4-0l-3-oic acid.

4. Gycloartenonc acid. 40. 3,4-seco-28-nor-cycloai'tenane-4-one- 3-oic acid. 5a. 3,4-deso-oleanane-i-ol-3-oic-acid. 5b. 3,4-seco-A -0leanene-3-0ic acid. 5c. 3 a4-seco-23-nor-oleananei-one-3-oic acl 5. Olcanane-B-onc Starting Materials Final Products 6. a-Amyri11e-12,13-0xide 6a. l2,13-0xido-3,4 sec0-ursane-4-0l-3-cic- (3b. 12,13-oxid0-3A-seco-N -urSauc-3- oic acid.

60. 12,13-0xido-3,4-seco-23-nor-ursane'4- one-3-oic acid.

7a. 3,4-scco-taraxastane-4-ol-3-oic acid.

7b. 3,4-seco-A (23 -taraxastene-It-oic acid.

70. 3,4-seco-23-nor-taraxastane-4-one-3- oic acid.

8a. 3,4-seco-taraxanc-4-ol-3-oic acid.

810. 3,4-seco-A (23 -taraxcne-3-oic acid.

80. 3f,4sec0-23-11or-taraxane-4-0ne-3-oic 7. Dchydrotaraxastcrol 8. Dchydrotaraxeronc acid. 95.. 3,4 seco-friedelane-4-o1-3-oic acid. 10a. 3,4-sec0-a1nusane-4-ol-3-oic-acid. 10b. 3,4-seco-A (23 -alnusene-S-oic acid. 10c. $21,4-sec0-23-n0r-a1nusane-4-one-3-oic acl 0. Friedcline 10. Alnusonyl Acetate U.S. C1. X.R.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Page n 3,483,225 Dated December 9, 1969 Inv.ntf(g) Gerald W. Krakower et al.

It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Column 2, line 45, the formula should be Ra Column 2, line 55, the formula should be:

Rllog A R Ra Ra Column 4, line 61, 5,75" should read5. 75-. Column 5, line 65 "Wood 5" should read-Woods-. Column 9, line 17, -lampstane" should read- -lanostene--. Column 9, line 23, -tirucallane" should read-- tirucallene-. Column 9, line 28, "deso" should read--seco.

Signed and sealed this 7th day of September 1971.

(SEAL) Attest:

EDWARD M.FLETGHER,JR.

testing Officer ROBERT GOTTSCHALK Acting Commissioner of Pater 

